Update app.py

app.py

@@ -13,6 +13,7 @@ language_dict = {
     "Guy": "en-US-GuyNeural",
     "Ana": "en-US-AnaNeural",
     "Aria": "en-US-AriaNeural",
+    "Brian": "en-US-BrianNeural",
     "Christopher": "en-US-ChristopherNeural",
     "Eric": "en-US-EricNeural",
     "Michelle": "en-US-MichelleNeural",